Arrangement for forming code marks

ABSTRACT

RECTANGULAR CODE MARKS ARE FORMED ON A PHOTOSENSITIVE MEDIUM SUCH AS A PHOTOGRAPHIC FILM OR XEROGRAPHIC PLATE OR WEB BY EXPOSING THE MEDIUM TO A CATHODE-RAY TUBE. THE MARKS ARE DISPLAYED ON THE CATHODE-RAY TUBE. THE LISSAJOUS-TYPE PATTERNS AND LETTING THEM RUN WITHIN THE CONSTRAINT OF THE DIMENSIONS OF THE RECTANGLE TO BE FORMED. IF THE TWO FREQUENCIES ARE SEPARATED BY NONINTEGRAL MULTIPLES, THE LISSAJOUS-TYPE PATTERNS WILL QUICKLY FILL THE RECTANGLE, AT WHICH TIME A NEW PATTERN MAY BE INITIATED.

United States Patent [72] lnventors [22] Filed Apr. 26, 1968 [45] Patented June 28, 197] [73] Assignee Eastman Kodak Company Rochester, N.Y.

[54] ARRANGEMENT FOR FORMING CODE MARKS [56] References Cited UNITED STATES PATENTS 2,985,065 /1961 Haynes 355/ Primary Examiner-John M. Horan Attorneys-Robert W. Hampton and Daniel E. Sragow ABSTRACT: Rectangular code marks are formed on a photosensitive medium such as a photographic film or xerographic plate or web by exposing the medium to a cathode-ray tube. The marks are displayed on the cathode-ray tube by forming Lissajous-type patterns and letting them run within the constraint of the dimensions of the rectangle to be formed. If the two frequencies are separated by nonintegral multiples, the Lissajous-type patterns will quickly fill the rectangle, at which time a new pattern may be initiated.

DATA

6 Claims, 3 Drawing Figs.

[52] U.S. Cl 95/].1, 355/ [51 Int. Cl G03b 17/24 Field ofSearch /l.1; 355/20, 40

,l4 ,12 IS HORIZ. gg WIDTH 055%.

i HOZlLj l 1 P05. 1 i L-o 5 4 5 I COMPUTER w 7 l i veer. u 1 P08 VERT. VERT- HEIGHT 0 FL I A me.

\IS \l3 l7 SOURCE PATENTED JUN28 |97| SHEET 2 UF 2 TO DEFLECTION AMPLIFIER FLIP-FLOP FIG.2

DONALD R. BREWER ASGER T. NIELSEN FIG.3

Q INVENT Rs BY fa duh 2a ATTORNEYS ARRANGEMENT FOR FORMING CODE MARKS BACKGROUND OF THE INVENTION In the prior art it is well known to use a cathode-ray tube for displaying information to be photographed or otherwise recorded. It is also well known to place code marks on the photosensitive medium in the vicinity of the information which has been recorded. In the prior art these code marks have been formed by exposing the photosensitive medium to lamps which are arranged in the pattern of the code. This has required additional equipment and limits the number of codes to the permutations and combinations of the lamp positions.

SUMMARY OF THE INVENTION It is therefore an object of the invention to provide a code marking arrangement which uses the cathode-ray tube itself.

It is a further object of the invention to provide a code marking apparatus which is simple and inexpensive but offers a great variety of code marking arrangements.

These and other objects of the invention are attained by drawing Lissajous-type figures on the cathode-ray tube using a signal generator for each of the deflection coordinates. If the frequencies of the two generators are made nonintegral multiples of each other, a' filled in rectangle is formed within the limitations of the deflection. The rectangle is then formed merely by switching on the generators for a predetermined period of time which is long enough to sufficiently expose the photosensitive medium.

The use of code marks is well known for identification purposes. Typical arrangements are shown in U.S. Pat. No. 3,290,987, issued Dec. 13, I966, to James et al.

BRIEF DESCRIPTION OF THE DRAWING Other objects and advantages of the invention will be apparent from the following description when taken with the drawing in which:

FIG. I is a block diagram of a system for displaying code marks on the face of the cathode-ray tube,

FIG. 2 is a simplified schematic diagram ofa single triangular wave generator for a particular coordinate, and

FIG. 3 is a chart showing the wave shapes at variouspoints in the triangular wave generator.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. I there is shown a data source I, which may be any well-known source of data, which is to be recorded onto a photosensitive medium 2 such as a photographic film, or a xerographic plate or web. The information from data source 1 is fed to computer 3 which determines the information needed to display the data from data source 1. The horizontal position is determined and fed from output 4 through the horizontal position amplifier I0. The vertical position is similarly determined and fed from output 9 to the vertical position amplifier 11. The width and height of the code marks are similarly determined and fed to the width and height amplifiers I2 and 13 from output terminals 5 and 8 respectively. The computer also determines the time during which the horizontal and vertical oscillators I4 and I5 operate to provide signals of a triangular waveform. This control is derived from output terminals 6 and 7 of the computer.

The outputs of oscillators I4 and are fed through width and height amplifiers 12 and 13 respectively to the respective deflection amplifiers 16 and 17 and then to the deflection yoke 18. The deflection yoke 18 is used with a conventional cathode-ray tube 19 and lens 20 for projecting the image drawn on the cathode-ray tube 19 onto photosensitive surface 2.

FIG. 2 shows a simplified schematic diagram of a triangular wave generator which would be used either as the horizontal oscillator or the vertical oscillator of FIG. 1. Clock pulses are fed to terminal C of flip-flop 100 at a high repetition rate. The

output of flip-flop 100 is fed through terminal F and resistor R, to the input of operational amplifier 101. Since the operational amplifier. 101 is bridged by capacitor C, it acts as an integrator. A source of negativepotential is connected through resistor R to the input of operational amplifier 101. This enables the output of the operational amplifier 101 to go either positive or negative in accordance with a positive or negative input. Transistors Q, and 0,- act as conventional amplifier inverters. The output of operational amplifier 101 is fed through resistor R, to the base of NPN transistor 0,. R is connected from the base of Q, to the collector of transistor Q, in order to provide negative feedback. Resistor R, acts as the collector resistor for transistor 0,. The output of transistor 0, is taken from its collector and fed through resistor R, to the base of NPN transistor 0,. At the same time the output of transistor Q, is fed through resistor R, to terminal J of flip-flop 100. Transistor Q, operates in a manner similar to transistor 0,. Its output goes through resistor R, to the K terminal of flip-flop 100. Potentiometers P, and P, are provided to control the voltage drop from terminals J and K to ground.

The operation of the triangular wave generator will better be understood with reference to FIG. 3. Waveshape C shows the voltage amplitude of the clock pulses as they come to terminal C of the flip-flop 100. Waveshape F shows the voltage amplitude of the terminal F of flip-flop 100. Waveshape J shows the voltage amplitude of terminal J of flip-flop 100, and Waveshape K shows the voltage amplitude at terminal K of flip-flop 100.

Assuming that the flip-flop 100 starts off in such a state that the signal provided at terminal F is positive, the output signal derived from the operational amplifier 101 which is bridged by capacitor C, starts going negative. Transistor Q, therefore gets more positive until the voltage at the J terminal of flipflop 100 gets high enough to cause it to change its state when the next clock pulse occurs. As can be seen from FIG. 3, the voltage at terminal J rises linearly until it reaches a certain point at which time it causes the voltage on terminal F to abruptly drop. At the same time, the voltage on the base of transistor 0 is increasing, thus tending to increase the conductivity of transistor 0, and to lower the collector voltage of transistor 0,. Therefore the voltage at terminal K of flip-flop 100 drops as shown in FIG.'3. When the flip-flop 100 changes its state, terminal F becomes negative, and the output of operational amplifier 101 now starts to go positive, etc.

The output of thetriangular wave generator has been shown in FIG. 2 to be taken from the output of operational amplifier 101. It is readily apparent, however, that the output could be just as easily taken from the collector of transistor Q, or the collector of transistor 0 Potentiometers P, and P regulate the potential which is applied to terminals J And K respectively of flip-flop 100. Regulations of this voltage affects the point at which the flip-flop changes its state.

In order to adjust the frequency of the triangular wave generator, capacitor C, has been shown to be variable. The

change in the value of capacitor C, changes the rate at which v the voltage at the output of operational amplifier 101 changes.

FliP-flop can be any of many available types. One type is the Motorola MC853 integrated circuit.

It is readily apparent that the invention can be used for forming other rectangles than merely code marks. For instance. the invention could easily be adapted to draw bar graphs, or the like.

The invention has been described using triangular wave generators for both the vertical and horizontal deflection components. It has been found, however, that the invention can also be practiced by using generators which produce different waveshapes for the horizontal and vertical components. For instance, one arrangement which has been found to operate satisfactorily uses a sine wave generator for vertical deflection, and a triangular wave generator for horizontal deflection. Of course, it is within the contemplation of the invention to use any combination of signal generators to form the Lissajous-type figures.

Although the invention has been described in considerable detail with reference to a certain preferred embodiment thereof, it will be understood that variations and modifications can be effected without departing from the spirit and scope of the invention.

We claim:

1. Apparatus for producing code marks comprising:

a. a cathode-ray tube having means for producing an electron beam; and

b. first and second means for deflecting the beam in two orthogonal directions, respectively;

c. a first wave generator having a first frequency rate, and being coupled to said first means for beam deflection; and

d. a second wave generator having a frequency rate which is a nonintegral multiple of the frequency rate of said first wave generator, and being coupled to said second means for beam deflection.

2. An apparatus as in claim 1, wherein said wave generators are triangular wave oscillators.

3. Apparatus for producing indicia marks, said apparatus comprising:

a. display means having first and second inputs;

b. first signal means for applying a first periodic signal having a first frequency rate to said first input of said display device; and

c. second signal means for applying a second periodic signal having a second frequency rate to said second input of said display device, the second frequency rate being a nonintegral multiple of the first frequency rate.

4. Apparatus for producing indicia marks on a radiation sensitive medium, said apparatus comprising:

a. an electron display device having means for producing an electron beam, and first and second means for deflecting the electron beam;

b. first signal means for applying to said first deflection means a first periodic signalhaving a first frequency rate; and

. second signal means for applying to said second deflec- 5. Apparatus as claimed in claim 4, wherein there is further included means for directing the displayed Lissajous-type figures onto the radiation sensitive medium.

6. Apparatus as claimed in claim 4, wherein each of said first and second signal means include:

a. bistable circuit means having first and second states and including first and second enabling inputs, said first enabling input responsive to enable said bistable circuit means to change from said first to said second state, said second enabling input responsive to enable said bistable circuit means to change from said second state to said first state to provide a first periodic output signal;

b. integrator circuit means coupled to said bistable circuit means for integrating the first output signal and to provide a second output signal indicative thereof; and

. inverter circuit means responsive to the second output signal for providing third and fourth output signals respectively to said first and second enabling inputs, the third output signal being inverted with respect to the fourth output signal. 

